The return of the Classic Environment

Despite Apple's decision to remove the Classic Environment from OS X "Leopard" 10.5.x and higher, demand for the classic OS 8 and 9 environment remains strong.

Users have requested that Apple reinstate the Classic Environment once more. Apple Inc. has refused, partly on the grounds that it is working with Adobe Systems Inc. to force all users to purchase the latest Adobe products (given the high expense and the allegedly high piracy rates for the software), and partly because it claims too much work and money is required to keep the software supported.

Installing SheepShaver

Despite Apple's refusal, users have discovered a third-party solution designed to run the Classic Environment on all Intel Macs.

SheepShaver 2.4 — a universal binary freeware emulation application for running Mac OS 9.0.4 (or 8.6 or 7.x) — will emulate at high speeds on PowerPC computers, although a minimum of 2.4GHz microprocessor (and preferably 2.8GHz) on an Intel Mac is recommended to get the same performance. This latest build is also compatible with OSX 10.8 "Mountain Lion". For a simplified version of SheepShaver for the Mac, try this link. There is also SheepShaver for Windows available here.

Here are the instructions for installing and running SheepShaver:

What you will need

  1. Naturally, you will need a copy of the latest stable universal binary SheepShaver 2.4 updated and released on 15 July 2012, downloadable from NOTE: SheepShaver build versions dated 6 and 7 November 2010 are not considered stable enough for running Adobe applications. Stick with the 25 October 2010 build. Or get the latest 15 July 2012 build as this has a PRAM zap script tool to clear the nvram preference file and allow a fresh one to be created by this latest build. Then it seems Adobe applications such as Illustrator 9.0 will run and quit without any sudden quit of SheepShaver. Remember, downloading and installing this software will not automatically run Classic OS9 software. You still need a couple of more essential software tools.
  2. The first additional software tool is a Mac OS 9 installation CD. It must be the original OS 9.0, not 9.1 or 9.2.x. You may need to ask a friend to borrow this, or see if a copy exists on a cloud server by a friendly user (but don't tell Apple, Inc. about it, okay?).
  3. Apply the free Mac OS 9.0.4 Update (don't try to find an update version higher than this or it won't work with SheepShaver), downloadable from (unless Apple has decided to do away with it, in which case, download it from here).
  4. The second additional software tool is a copy of a suitable New World Mac OS ROM file. We recommend using the most stable MacOS ROM 1.6 from the MacOS ROM Update 1.0 for OS 9, downloadable from Alternatively download from here for OS 8.6. Use the utility TomeViewer 1.3d3 on a PowerPC Mac running Classic Environment to extract the ROM from the Apple OS installer file. NOTE: For Intel users, this is not possible. Therefore download the COI Chubby Bunny 4.0.1 update (54MB) and a tool to turn on invisible files on your hard disk. With option key down, click on the application and choose "Show Package Contents". Navigate to within the folder to find the ROM file, rename it as "MacOS9.rom" and drag it out into the SheepShaver folder.
  5. Adequate space on your hard disk to create the (macos9.dmg) image disk for storing a copy of the Mac OS 9 system folder and various classic applications of your choosing.

If you have trouble obtaining the essential files, you can download them from here (5.8MB). But remember, you will need to find an OS 9 installation CD to install the System Folder. As not everyone has the installation CD (and Apple is unlikely to have any left for sale) you can alternatively extract a ready-made disk with the OS9 system folder installed through the COI Chubby Bunny 4.0.1 update (54MB). We suggest you rename the image disk as "macos9.dmg". Alternatively, check some of the Computer Fairs to see if an old OS9 system disk is available.

How to install

  1. Place the ready-to-use SheepShaver folder into your OS X Applications folder. Rename the folder as SheepShaver.
  2. Remember to keep and inside the folder. You will need these files.
  3. If you have extracted the ROM file from the MacOS ROM Update 1.0 archive, place the ROM file inside the SheepShaver folder. Rename the file to MacOS.rom.
  4. Launch You will be greeted with the SheepShaver Settings dialog box.
  5. If the macos9.dmg file is not in your SheepShaver folder, click the Create button in the Setup tab. By doing so, you will be creating the macos9.dmg file for storing the Mac OS 9 System Folder and Applications. Set the size to, say, 1000MB (i.e. 1GB). Save the file in your SheepShaver folder. Click the Save button.
  6. After about 10 seconds, SheepShaver GUI will have completed its task of creating macos9.dmg. NOTE: Alternatively, open Terminal and type: dd if=/dev/zero of=macos9.dmg bs=1024k count=1000, where count=1000 is the size of the disk image in megabytes. Pressing return and waiting for about 30 seconds will create the empty disk image in your Home folder.
  7. Set the RAM size for running SheepShaver to 1024MB. You shouldn't need more than this.
  8. To specify the path to the ROM file, type MacOS.rom if the file is located in the SheepShaver folder.
  9. In the Unix Root field, type /Users/Shared/. This is the folder location from where you can exchange files and applications between OS X and OS9.
  10. In the Boot From field, select Any. If you just want to boot from a CD, choose CD-ROM, but you'll find it quicker later to store a copy of the OS9 System Folder inside macos9.dmg.
  11. In the Audio/Video tab, set Window Refresh Rate to 60Hz (for PPC users, set this to below 30Hz or else it will hog too much CPU time processing the extra video information and your computer will get too hot). Choose Video Type "Window" and choose a window width and height. For fullscreen mode using the native resolution of your screen, set both width and height to 0, choose "Fullscreen" for the Video Type and set the Refresh Rate to 30Hz (or as little as 15Hz, but the cursor will move in a slightly jerky fashion). It should work like a treat.
  12. In the Miscellaneous tab, type slirp for the Ethernet Interface. This will let you share OS X's network connection.
  13. For Modem Port Device, type /dev/cu.Bluetooth-Modem
  14. For Printer Port Device, type /dev/null.
  15. In the Setup tab, select Boot From CD-ROM.
  16. Insert the Mac OS 9 installation CD. Alternative, if you already have a System Folder prepared (i.e. version 9.0 to 9.0.4), burn this on a CD as a bootable disk.
  17. Click the Start button (or close the SheepShaver GUI and launch to commence emulation mode
  18. A window showing a diskette in the middle and a flashing question mark will appear. This tells you it is looking for a Mac OS 9 System Folder to boot from. A second or two later, it will show a smiley face as it boots from the CD.
  19. You will reach the OS9 desktop. A question will be asked whether to initialise the hard disk (i.e. stored in macos9.dmg). Select "Extended File Format" and click Initialise.
  20. Follow the instructions for installing Mac OS 9 on the new OS9 hard disk. Alternatively, if you have already booted from a System Folder, copy this folder directly to the OS 9 hard disk.
  21. When you shutdown, select Boot From Any in You should now be able to boot off the Mac OS 9 System Folder inside macos9.dmg.
  22. Your OS X startup disk will appear on the Mac OS 9 desktop as Unix. Use it to transfer files and applications back and forth as you require.

A few tips

Another thing to remember. Never try to open macos9.dmg through Disk Utility on OS X and write files to it. Otherwise it will cause an error followed by the destruction of the OS 9 disk format. It this happens, you will have to rebuild macos9.dmg from scratch.

Also consider going into (i) the Energy Saver control panel under OS9 and set the options to "Never" to solve an issue regarding the cursor suddenly hanging after a while; and (ii) the Appearance control panel and choose "None" for the sound track in the Sound tab as it seems "Platinum Sounds" are likely to crash SheepShaver. Likewise on Intel Macs, opening and using ScrapBook may also crash SheepShaver.

Don't use Disk Warrior 2.1 or other disk tools (including Disk Copy) to optimise the OS 9 disk. It changes the disk in such a way that it no longer provides stability under SheepShaver.

If you use ResEdit, you can change the "vers" (i.e. version) number of the Finder and System files to 9.1 (as opposed to 9.0.4). The system will still run under SheepShaver but will have the added benefit of installing additional OS9 applications you thought was not possible unless you had the genuine OS 9.1 version. This includes Adobe Photoshop 7.0 except only Adobe ImageReady 7.0 will work. Change version number of QuickTime and QuickTime PowerPlug to 4.1.2 or higher and you will be able to install AppleWorks 6. Or find a copy of QuickTime 4.1.3 to install.

And if you have put your computer to sleep and later woke it up and try to run SheepShaver and an application such as Adobe Photoshop 5.5, it may get stuck in an endless loop showing a dialog box about not being able to accept or clear the clipboard. You'll need to restart the computer to solve the problem.

Good luck, and happy OS9 computing!

NOTE: Emulation is a highly processor intensive activity and is likely to overheat your PPC and single- or dual-core Intel Macs (just like the high heat generated by the audio file processor intensive work experienced by users on the early 2009 Mac Pro for which Apple has finally issued a fix in February 2010). So please keep usage of SheepShaver to a minimum, or set the refresh rate to no higher than 30Hz (even 15Hz is fine). Alternatively use a smaller window size.